Touché

A doorknob that knows to lock or unlock based on how it is grasped. A smartphone that silences itself if the user holds a finger to her lips. A chair that adjusts room lighting.

They are among the many possible applications of Touché, a new sensing technique developed by a team at Disney Research, Pittsburgh, and Carnegie Mellon University.

Touché is a form of capacitive touch sensing, the same principle underlying the types of touchscreens used in most smartphones.

But instead of sensing electrical signals at a single frequency, like the typical touchscreen, Touché monitors capacitive signals across a broad range of frequencies.

This Swept Frequency Capacitive Sensing (SFCS) makes it possible to not only detect a "touch event," but to recognize complex configurations of the hand or body that is doing the touching. An object thus could sense how it is being touched, or might sense the body configuration of the person doing the touching.

SFCS is robust and can enhance everyday objects by using just a single sensing electrode. Sometimes, as in the case of a doorknob or other conductive objects, the object itself can serve as a sensor and no modifications are required.

Even the human body or a body of water can be a sensor.

"Signal frequency sweeps have been used for decades in wireless communication, but as far as we know, nobody previously has attempted to apply this technique to touch interaction," said Ivan Poupyrev, senior research scientist at Disney Research, Pittsburgh.

"Yet, in our laboratory experiments, we were able to enhance a broad variety of objects with high-fidelity touch sensitivity. When combined with gesture recognition techniques, Touché demonstrated recognition rates approaching 100 percent.

That suggests it could immediately be used to create new and exciting ways for people to interact with objects and the world at large."

In addition to Poupyrev, the research team included Chris Harrison, a Ph.D. student in Carnegie Mellon's Human-Computer Interaction Institute, and Munehiko Sato, a Disney intern and a Ph.D. student in engineering at the University of Tokyo.

The researchers will present their findings May 7 at CHI 2012, the Conference on Human Factors in Computing Systems, in Austin, Texas, where it has been recognized with a prestigious Best Paper Award.

Disney Research, Pittsburgh is located on CMU's campus in the Robert Mehrabian Collaborative Innovation Center. This building also houses technology research and development offices for Apple and Intel as well as CMU's CREATE Lab, Cylab and CERT® Coordination Center.